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BACKGROUND: Pulmonary hypertension (PH) is associated with aberrant sympathoexcitation leading to right ventricular failure (RVF), arrhythmias, and death. Microglial activation and neuroinflammation have been implicated in sympathoexcitation in experimental PH. We recently reported the first evidence of thoracic spinal cord (TSC) neuroinflammation in PH rats. Here, we hypothesize that PH is associated with increased cardiopulmonary afferent signaling leading to TSC-specific neuroinflammation and sympathoexcitation. Furthermore, inhibition of TSC neuroinflammation rescues experimental PH and RVF. METHODS: We performed transcriptomic analysis and its validation on the TSC of monocrotaline (n=8) and Sugen hypoxia (n=8) rat models of severe PH-RVF. A group of monocrotaline rats received either daily intrathecal microglial activation inhibitor minocycline (200 μg/kg per day, n=5) or PBS (n=5) from day 14 through 28. Echocardiography and right ventricle-catheterization were performed terminally. Real-time quantitative reverse transcription PCR, immunolocalization, microglia+astrocyte quantification, and terminal deoxynucleotidyl transferase dUTP nick end labeling were assessed. Plasma catecholamines were measured by ELISA. Human spinal cord autopsy samples (Control n=3; pulmonary arterial hypertension n=3) were assessed to validate preclinical findings. RESULTS: Increased cardiopulmonary afferent signaling was demonstrated in preclinical and clinical PH. Our findings delineated common dysregulated genes and pathways highlighting neuroinflammation and apoptosis in the remodeled TSC and highlighted increased sympathoexcitation in both rat models. Moreover, we validated significantly increased microglial and astrocytic activation and CX3CL1 expression in TSC of human pulmonary arterial hypertension. Finally, amelioration of TSC neuroinflammation by minocycline in monocrotaline rats inhibited microglial activation, decreased proinflammatory cytokines, sympathetic nervous system activation and significantly attenuated PH and RVF. CONCLUSIONS: Targeting neuroinflammation and associated molecular pathways and genes in the TSC may yield novel therapeutic strategies for PH and RVF.

This study aimed to investigate the diagnosis and treatment of thoracic anterior spinal cord herniation, a rare condition. Clinical data of 7 patients diagnosed with thoracic anterior spinal cord herniation were analyzed. All patients were diagnosed with a complete preoperative examination and scheduled for surgical treatment. In addition, regular follow-up was performed after the surgery, and the operation's efficacy was evaluated according to clinical symptoms, imaging findings, and improvement in neurologic function. All patients underwent spinal cord release with an anterior dural patch. Notably, no severe postoperative surgical complications were observed. All patients were followed up for 12–75 months, with an average duration of approximately 46.5 months. Post-operative pain symptoms were controlled, neurological dysfunction and related symptoms improved to varying degrees, and anterior spinal cord herniation did not recur. The modified Japanese Orthopedic Association score at the last follow-up was significantly higher than the preoperative score. Clinicians should avoid misdiagnosing patients with thoracic anterior spinal cord herniation with intervertebral disc herniation, arachnoid cysts, and other related diseases, and patients should undergo surgical treatment as early as possible. In addition, surgical treatment can protect the neurologic function of patients and effectively prevent the aggravation of clinical symptoms. [ABSTRACT FROM AUTHOR]

Unwanted proteins and metabolic waste in cerebral spinal fluid are cleared from the brain by meningeal and nasal lymphatics and the perineural sheath of cranial nerves; however, the distribution and clearance of cerebral spinal fluid (CSF) along the subarachnoid space of the entire spinal cord is not fully understood. Cryo-fluorescence tomography (CFT) was used to follow the movement of tracers from the ventricular system of the brain down through the meningeal lining of the spinal cord and out to the spinal lymphatic nodes. Isoflurane-anesthetized mice were infused into the lateral cerebroventricle with 5.0 µL of quantum dots [QdotR 605 ITKTM amino (PEG)] over two mins. Mice were allowed to recover (ca 2–3 min) and remained awake and ambulatory for 5, 15, 30, 60, and 120 min after which they were euthanized, and the entire intact body was frozen at −80°. The entire mouse was sectioned, and white light and fluorescent images were captured after each slice to produce high resolution three-dimensional volumes. Tracer appeared throughout the ventricular system and central canal of the spinal cord and the entire subarachnoid space of the CNS. A signal could be visualized in the nasal cavity, deep cervical lymph nodes, thoracic lymph nodes, and more superficial submandibular lymph nodes as early as 15 min post infusion. A fluorescent signal could be visualized along the dorsal root ganglia and down the proximal extension of the spinal nerves of the thoracic and lumbar segments at 30 min. There was a significant accumulation of tracer in the lumbar and sacral lymph nodes between 15–60 min. The dense fluorescent signal in the thoracic vertebrae noted at 5- and 15-min post infusion was significantly reduced by 30 min. Indeed, all signals in the spinal cord were ostensibly absent by 120 min, except for trace amounts in the coccyx. The brain still had some residual signal at 120 min. These data show that Qdots with a hydrodynamic diameter of 16–20 nm rapidly clear from the brain of awake mice. These data also clearly demonstrate the rapid distribution and efflux of traces along a major length of the vertebral column and the potential contribution of the spinal cord in the clearance of brain waste. [ABSTRACT FROM AUTHOR]

Background: Capillary hemangiomas are typically superficial benign tumors of the cutaneous and mucosal tissues of the face and neck in pediatric patients. In adults, they typically occur in middle-aged males who present with pain, myelopathy, radiculopathy, paresthesias, and bowel/bladder dysfunction. The optimal treatment for intramedullary spinal cord capillary hemangiomas is gross total/en bloc resection. Methods: Here, we present a 63-year-old male with increasing right greater than left lower extremity numbness/weakness, attributed to a T8-9 mixed intra- and extramedullary capillary hemangioma. Results: One year following complete lesion resection, the patient used an assistive device to ambulate and continued to improve neurologically. Conclusion: We presented a 63-year-old male whose paraparesis was attributed to a T8-9 mixed intra- and extramedullary capillary hemangioma who did well following total en bloc lesion resection. In addition to this case study/technical note, we provide a 2-D intraoperative video detailing the resection technique. [ABSTRACT FROM AUTHOR]

Occurrence of intramedullary schwannomas is rare as Schwann cells are generally present in the nerve root and not in the spinal cord. To date, approximately around 60 cases of intramedullary schwannoma in patients without neurofibromatosis have been reported in the English literature, of which only eight were children. We describe two cases of thoracic intramedullary schwannomas that recurred after primary excision. A 10 years old boy presented with weakness of both lower limbs. Magnetic resonance imaging showed a D10 to D12 intramedullary lesion, which was excised near totally and confirmed to be a schwannoma on histopathological examination. The tumour recurred twice after that and was re operated both times. Another 57 years old lady presented with weakness of both lower limbs and a history of being operated in the past for D9-D10 intramedullary lesion. She was re-operated with total removal of the lesion confirmed to be schwannoma on histopathological examination. Intramedullary schwannoma may recur after resection. [ABSTRACT FROM AUTHOR]

Abstract The Pilomyxoid is rare tumor in elderly population, in addition to the occurrence of an isolated lesion in spinal cord is extremely rare in non‐pediatric population. Taking biopsy and subtotal resection is the starting point in essential approach for the treatment. After defining the histopathological nature of the tumor and specified that is Pilomyxoid, the next step is the combination of reoperation and adjuvant therapy.

Introduction: White cord syndrome (WCS) is a rare phenomenon which causes acute neurologic deterioration after a chronically compressed spinal cord is surgically decompressed, resulting in a T2-hyperintense signal to appear in the cord. We present the first case of pediatric WCS in the thoracic spine and the first to show complete resolution of symptoms. Case Presentation: A 3-year-old girl presented with difficulty ambulating due to pain caused by T4-8 spinal cord compression from a mass of ganglioneuromatous tissue, consistent with her previously treated mediastinal neuroblastoma. She underwent laminoplasty and microsurgical debulking of the mass. She developed severe bilateral leg weakness on postoperative day 1. Magnetic resonance imaging (MRI) showed T2 hyperintensity in the spinal cord from T1 to T10 without enhancement, concerning for WCS. She was started on high-dose steroids and monitored. Her strength improved to 3/5 in both legs prior to discharge to inpatient rehabilitation. On the latest follow-up, 4 months after surgery, she did not demonstrate any neurologic deficits and was ambulating well. Follow-up MRIs have showed continued improvement in the T2 hyperintensity. Discussion/Conclusion: Most cases in the literature occur in older adults with chronic cervical compression. Only 1 pediatric case, caused by a cervical arachnoid cyst, has been reported and only resulted in partial improvement. Our case is the first pediatric case of WCS to occur in the thoracic spine, the first pediatric case to demonstrate complete resolution, and the first case of any age to start to establish a length of time the compression is needed to be at risk for WCS. [ABSTRACT FROM AUTHOR]

The Pilomyxoid is rare tumor in elderly population, in addition to the occurrence of an isolated lesion in spinal cord is extremely rare in non‐pediatric population. Taking biopsy and subtotal resection is the starting point in essential approach for the treatment. After defining the histopathological nature of the tumor and specified that is Pilomyxoid, the next step is the combination of reoperation and adjuvant therapy. [ABSTRACT FROM AUTHOR]

Expiratory neurons in the caudal ventral respiratory group extend descending axons to the lumbar and sacral spinal cord, and they possess axon collaterals, the distribution of which has been well-documented. Likewise, these expiratory neurons extend axons to the thoracic spinal cord and innervate thoracic expiratory motoneurons. These axons also give rise to collaterals, and their distribution may influence the strength of synaptic connectivity between the axons and the thoracic expiratory motoneurons. We investigated the distribution of axon collaterals in the thoracic spinal cord using a microstimulation technique. This study was performed on cats; one cat was used to make an anatomical atlas and six were used in the experiment. Extracellular spikes of expiratory neurons were recorded in artificially ventilated cats. The thoracic spinal gray matter was microstimulated from dorsal to ventral sites at 100-μm intervals using a glass-insulated tungsten microelectrode with a current of 150–250 μA. The stimulation tracks were made at 1 mm intervals along the spinal cord in segments Th9 to Th13, and the effective stimulating sites of antidromic activation in axon collaterals were systematically mapped. The effective stimulating sites in the contralateral thoracic spinal cord with expiratory neurons in the caudal ventral respiratory group (cVRG) occupied 14.4% of the total length of the thoracic spinal cord examined. The mean percentage of effective stimulating tracks per unit was 18.6 ± 4.4%. The distribution of axon collaterals of expiratory neurons in the feline thoracic spinal cord indeed resembled that reported in the upper lumbar spinal cord. We propose that a single medullary expiratory neuron exerts excitatory effects across multiple segments of the thoracic spinal cord via its collaterals. • Cats' expiratory neurons have axon collaterals in the thoracic spinal cord. • We used a microstimulation technique to find the axon collaterals of single expiratory neurons. • Expiratory neurons distributed axon collaterals in a wide area of the thoracic spinal cord. • That distribution appeared to be similar to that in the upper lumbar spinal cord. [ABSTRACT FROM AUTHOR]

Background and Importance: Epidermoid cyst in the spinal cord is a rare condition. It constitutes of only 0.6-1.1% of all spinal tumors. When they occur, the typical location is in the subdural, extramedullary space of the lumbo-sacral region. Case Presentation: We report a forty-two -year-old female who presented with left extremity radicular pain and myelopathy. MRI of the thoracic spine,illustrated a focal fusiform enlargement of the thoracic cord at T4 and T5. Histopathological examination confirmed the diagnosis of epidermoid cyst. Conclusion: The lesion was surgically resected and the pathology revealed we discuss the clinical features, MR imaging characteristics and surgical findings of this rare tumor and review the associated literature.

Hemangioblastomas of the posterior cranial fossa and spinal cord in adults are excessively vascularized, well-differentiated, and scarce tumors with no metastatic potential. This paper discusses its surgical management and outcome, pointing out their morphological, radiological, and histopathological aspects. This report based on a personal series of six patients and on a literature review. A single-institution personal 6-case series of adult patients diagnosed and operated on by a senior neurosurgeon (KIA) due to posterior cranial fossa or spinal cord hemangioblastoma was analyzed. For easier understanding of hemangioblastoma, we have classified them into four different types. The tumors, which were all surgically treated, were located in the posterior cranial fossa in five patients (4 cerebellar, 1 brain stem) and intramedullary in the thoracic spinal cord in one patient. All patients successfully recovered neurologically after a complete tumor resection, having no post-operative neurological deficit or other complications. Surgical management of cerebellar and spinal cord hemangioblastoma in adults is highly dependent on its morphological features, as well as on microsurgical technique applied. Since huge differences exist between the cystic/nodular tumor type (Type 1) and the solid type and its two additional variants (Types 2–4), morphology is the most important consideration when deciding surgical approach. Despite significant morphological differences among different subtypes of hemangioblastomas, their histology appears to be relatively similar. Nonetheless, a meticulous and refined surgical technique has to be utilized to achieve a successful outcome. [ABSTRACT FROM AUTHOR]

Background: Mechanisms associated with cervical spinal cord (CSC) and upper thoracic spinal cord (TSC) atrophy in multiple sclerosis (MS) are poorly understood. Objective: To assess the influence of brain, CSC and TSC T2-hyperintense lesions on cord atrophy and disability in MS. Methods: Thirty-four MS patients underwent 3T brain, cervical and thoracic cord magnetic resonance imaging (MRI) and Expanded Disability Status Scale (EDSS) score assessment. CSC/TSC lesion number and volume (LV), whole-brain and cortico-spinal tract (CST) LVs were obtained. Normalized whole CSC and upper TSC cross-sectional areas (CSAn) were also derived. Age- and sex-adjusted regression models assessed associations of brain/cord lesions with CSAn and EDSS and identified variables independently associated with CSAn and EDSS with a stepwise variable selection. Results: CSC CSAn (β = −0.36, p = 0.03) and TSC CSAn (β = −0.60, p < 0.001) were associated with CSC T2 LV. EDSS (median = 3.0) was correlated with CSC T2 LV (β = 0.42, p = 0.01), brain (β = 0.34, p = 0.04) and CST LV (β = 0.35, p = 0.03). The multivariate analysis retained CSC LV as significant predictor of CSC CSAn (R 2 = 0.20, p = 0.023) and TSC CSAn (R 2 = 0.51, p < 0.001) and retained CSC and CST LVs as significant predictors of EDSS (R 2 = 0.55, p = 0.001). Conclusions: CSC LV is an independent predictor of cord atrophy. When neurological impairment is relatively mild, central nervous system (CNS) lesion burden is a better correlate of disability than atrophy. [ABSTRACT FROM AUTHOR]

Highlights • Cardiac modulation of intercostal and abdominal EMG was found in anesthetized dogs. • Modest cardiac modulation of expiratory bulbospinal neuron discharges was also found. • The bulbospinal modulation was not sufficient to explain the EMG modulation. • Thoracic and abdominal muscle spindles may contribute to cardiac interoception. Abstract Previous analyses of recordings of alpha motoneuron discharges from branches of the intercostal and abdominal nerves in anesthetized cats under neuromuscular blockade demonstrated modulation with the cardiac cycle. This modulation was interpreted as evidence that thoracic somatosensory afferents, most likely muscle spindles, provide a signal to the CNS that could contribute to cardiac interoception. Here, two aspects of these observations have been extended. First, new measurements of thoracic and abdominal EMG activity in spontaneously breathing dogs show that a very similar modulation exists in these rather different circumstances. Second, further analysis of the cat recordings shows that cardiac modulation of the discharges of bulbospinal neurons that transmit the expiratory drive to thoracic motoneurons is weak and of an inappropriate time-course to be a contributor to the effect seen in the motoneurons. [ABSTRACT FROM AUTHOR]

There are hardly any published data on the characteristics of muscle nerve sympathetic discharges occurring in parallel with the somatic motoneurone discharges in the same nerves. Here, we take advantage of the naturally occurring respiratory activity in recordings of efferent discharges from branches of the intercostal and abdominal nerves in anesthetized cats to make this comparison. The occurrence of efferent spikes with amplitudes below that for alpha motoneurones were analyzed for cardiac modulation, using cross-correlation between the times of the R-wave of the ECG and the efferent spikes. The modulation was observed in nearly all recordings, and for all categories of nerves. It was strongest for the smallest amplitude spikes or spike-like waveforms, which were deduced to comprise postsynaptic sympathetic discharges. New observations were: (1) that the cardiac modulation of these discharges was modest compared to most previous reports for muscle nerves; (2) that the amplitudes of the sympathetic discharges compared to those of the somatic spikes were strongly positively correlated to nerve diameter, such that, for the larger nerves, their amplitudes overlapped considerably with those of gamma motoneurone spikes. This could be explained by random summation of high rates of unit sympathetic spikes. We suggest that under some experimental circumstances this overlap could lead to considerable ambiguity in the identity of the discharges in efferent neurograms. [ABSTRACT FROM AUTHOR]

Recordings of alpha motoneuron discharges from branches of the intercostal and abdominal nerves in anesthetized cats were analyzed for modulation during the cardiac cycle. Cardiac modulation was assessed by the construction of cross-correlation histograms between the R-wave of the ECG and the largest amplitude efferent spikes. In all but two recordings (which were believed to have either no or few alpha spikes), the histograms showed relatively short duration peaks and/or troughs (widths at half amplitude 4-50 ms) at lags of 10-150 ms. These observations were deduced to result from activity in oligosynaptic pathways, probably from muscle spindle afferents, whose discharges are known to be synchronized to the cardiac pulse. The results suggest that onward transmission of the cardiac signal from thoracic muscle afferents (and possibly from other dynamically sensitive afferents) to other parts of the central nervous system is highly likely and that therefore these afferents could contribute to cardiac interoception. [ABSTRACT FROM AUTHOR]

Functional magnetic resonance imaging (fMRI) of thoracic spinal cord neurons was used to examine the neural correlates of visceral emotional responses. Participants completed four spinal fMRI runs involving passive viewing (i.e. no movement) and motoric responses to negative or neutral images. Negative images, particularly in the movement condition, elicited robust activity in motoric nuclei, indicating 'action preparedness'. These images also enhanced activity in autonomic and sensory nuclei, thus providing a clear neural representation of visceral responses to emotional stimuli. [ABSTRACT FROM AUTHOR]

Internal intercostal and abdominal motoneurons are strongly coactivated during expiration. We investigated whether that synergy was paralleled by synergistic Group I reflex excitation. Intracellular recordings were made from motoneurons of the internal intercostal nerve of T8 in anesthetized cats, and the specificity of the monosynaptic connections from afferents in each of the two main branches of this nerve was investigated. Motoneurons were shown by antidromic excitation to innervate three muscle groups: external abdominal oblique [EO; innervated by the lateral branch (Lat)], the region of the internal intercostal muscle proximal to the branch point (IIm), and muscles innervated from the distal remainder (Dist). Strong specificity was observed, only 2 of 54 motoneurons showing excitatory postsynaptic potentials (EPSPs) from both Lat and Dist. No EO motoneurons showed an EPSP from Dist, and no IIm motoneurons showed one from Lat. Expiratory Dist motoneurons fell into two groups. Those with Dist EPSPs and none from Lat (group A) were assumed to innervate distal internal intercostal muscle. Those with Lat EPSPs (group B) were assumed to innervate abdominal muscle (transversus abdominis or rectus abdominis). Inspiratory Dist motoneurons (assumed to innervate interchondral muscle) showed Dist EPSPs. Stimulation of dorsal ramus nerves gave EPSPs in 12 instances, 9 being in group B Dist motoneurons. The complete absence of heteronymous monosynaptic Group I reflex excitation between muscles that are synergistically activated in expiration leads us to conclude that such connections from muscle spindle afferents of the thoracic nerves have little role in controlling expiratory movements but, where present, support other motor acts. [ABSTRACT FROM AUTHOR]

The objective of this paper is to mention the case of a 10 years old patient, managed in our hospital after suffering spinal cord injury with complete thoracic spinal cord injury (Frankel A), which improved significantly after receiving surgical management by decompression and stabilization by posterior instrumentation with sublaminar hooks plus early postoperative rehabilitation. A review of the current literature related to the condition and evolution of our patient is made. [ABSTRACT FROM AUTHOR]

Background: For successful DREZ (dorsal root entry zone) surgery, optimal neuroanatomical orientation and precise microsurgical dissection are required. Although cervical, lumbar, and sacral spinal segments have been studied in detail, such information is not available for thoracic segments. The objective of this anatomical study is to comprehensively illustrate the microanatomical features of the thoracic DREZs and their variations. Methods: Fifteen formalin-fixed adult cadaveric spinal cords from T1 to T12 were used. The dorsal rootlet numbers, distance between the posteromedial and posterolateral sulcus, length of each DREZ, length of each segment, and mean length of the dorsal rootlets were measured under a surgical microscope. Results: The longest DREZs were observed at the T6, T7, and T8 segments with mean values of 15.3 mm, 15.6 mm, and 15.4 mm, respectively. The longest segment was observed at the T10 segment with a mean value of 21.0 mm, and the shortest segment was observed at the T1 segment with a mean value of 13.5 mm. Conclusions: The highest dorsal rootlet density is at the T1 segment of the spinal cord, can be easily distinguished visually, and may be a useful surgical landmark. The DREZs in T6-7 segments are longest, while these two segments have the least number of rootlets. Because the dorsolateral tract is remarkably narrow and the dorsal horn is exceedingly deep, DREZ surgery at the thoracic level may be difficult and risky for the dorsal column and corticospinal tract. Acquaintance with the microanatomy of the DREZ in the thoracic spinal cord is crucial to DREZ surgery. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to examine spinal processing of cardiac and somatic nociceptive input in rats with STZ-induced diabetes. Type 1 diabetes was induced with streptozotocin (50mg/kg) in 14 male Sprague–Dawley rats and citrate buffer was injected in 14 control rats. After 4–11weeks, the rats were anesthetized with pentobarbital, ventilated and paralyzed. A laminectomy enabled extracellular recording of T3 spinal cord neuronal activity. Intrapericardial administration of a mixture of algogenic chemicals (bradykinin, serotonin, prostaglandin E2 (all at 10−5 M), and adenosine (10−3 M)) was applied to activate nociceptors of cardiac afferent nerve endings. Furthermore, somatic receptive properties were examined by applying innocuous (brush and light pressure) and noxious (pinch) cutaneous mechanical stimuli. Diabetes-induced increases in spontaneous activity were observed in subsets of neurons exhibiting long-lasting excitatory responses to administration of the algogenic mixture. Algogenic chemicals altered activity of a larger proportion of neurons from diabetic animals (73/111) than control animals (55/115, P<0.05). Some subtypes of neurons exhibiting long-lasting excitatory responses, elicited prolonged duration and others, had a shortened latency. Some neurons exhibiting short-lasting excitatory responses in diabetic animals elicited a shorter latency and some a decreased excitatory change. The size of the somatic receptive field was increased for cardiosomatic neurons from diabetic animals. Cutaneous somatic mechanical stimulation caused spinal neurons to respond with a mixture of hyper- and hypoexcitability. In conclusion, diabetes induced changes in the spinal processing of cardiac input and these might contribute to cardiovascular autonomic neuropathy in patients with diabetes. [Copyright &y& Elsevier]

Abstract: The availability of genetically manipulated mice offers a golden opportunity for the study of the contribution of the genome to diseases. Because of the technical difficulty in performing spinal subarachnoid catheterization in mice, this opportunity has hitherto been less harnessed in investigations on the role of the spinal cord in the physiological or pathological processes. Even less explored are spinal mechanisms that underlie cardiovascular regulation since subarachnoid catheterization of the mouse thoracic spinal cord, where preganglionic sympathetic neurons governing vasomotor tone are located posts the highest challenge because of the restricted operating area. We report a procedure for subarachnoid catheterization of the thoracic spinal cord in mice that did not require laminectomy or drilling of the lamina proper, and compared the suitability of two candidate catheters, polyethylene PE-5 catheter (0.51mm, OD) and polyurethane PU-10 catheter (0.25mm, OD). Whereas all implanted mice resumed normal feeding one day after surgery and were devoid of bladder dysfunction or self-mutilation, the smaller and softer PU-10 catheter compared favorably because of lower post-operative mortality rate and no unilateral lower limb paresis. [Copyright &y& Elsevier]

Spinal cord dissemination (metastasis) of a fourth ventricle ependymoma more than ten years after surgical resection is extremely rare. In this report, we present an unusual case of a fourth ventricle ependymoma with metastasis to the thoracic spinal cord 19 years after the initial therapy, but without local recurrence. A 37 year-old patient underwent gross total resection of a fourth ventricle ependymoma and postoperative radiation therapy to the posterior fossa. Computed tomography (CT) scanning and/or magnetic resonance (MR) imaging performed during follow up examinations, conducted annually for ten years after the therapy, revealed no evidence of local tumor recurrence. However, 19 years after the initial treatment, the patient complained of back pain and gait disturbances. MR imaging revealed an intradural extramedullary tumor at the Th2–5 levels. MR imaging of the brain revealed no local tumor recurrence or intracranial tumor dissemination. Cerebrospinal fluid cytology revealed no presence of tumor cells. Total resection of the spinal cord tumor was performed, and the tumor was diagnosed as an ependymoma. We describe the clinical features of this rare lesion and particularly emphasize the need for long-term follow up, for more than ten years after the initial treatment, in patients with fourth ventricle ependymoma. [ABSTRACT FROM AUTHOR]

Ossification of ligamentum flavum (OLF) is a well-known pathology causing myelopathy, although it is a rare disease. The most commonly affected population is from the Far East and mainly Japanese. However, few reports and studies have shown the prevalence of the disease all over the world. We report the case of a 33-year-old man presenting with signs of progressive myelopathy. Magnetic resonance imaging (MRI) showed Th2-Th11 OLF with severe narrowing and intramedullary hypersignal at the level Th2-Th3. This is the first Lebanese case reported in the literature. A decompressive laminectomy with flavectomy was done. This case adds to the previous reported cases on the occurrence of the disease in different populations. [ABSTRACT FROM AUTHOR]

Abstract: Background: Spinal cord herniation through a dural defect is a cause of myelopathy and BSS that may be underdiagnosed. It may occur spontaneously, after trauma, or after surgery. Case Description: We present the case of a 47-year-old woman who presented with low back pain, progressive myelopathy, right proximal LEW, several episodes of falling, sensory changes below the lower part of the chest wall, and pathologic reflexes. Magnetic resonance imaging of the thoracic spine showed kinking of the spinal cord anteriorly at the level of T6-7. Posterior laminoplasty and intradural exploration revealed an anteriorly displaced spinal cord that was herniating through a ventral dural fold. The defect was repaired, and the spinal cord abnormality was reduced. Postoperatively, the patient''s strength, gait, and sensation improved immediately. Conclusions: We discuss the successful surgical treatment of a thoracic spinal cord tethering from herniation through a ventral dural defect and review the literature regarding the proposed pathogenesis, surgical repair options, and reported outcomes. [Copyright &y& Elsevier]

Abstract: Background: Subpial intramedullary schwannoma of the spine is a rare tumor. A few case reports have revealed that the tumor originates from around the ventral nerve exit zone, with only one case confirming involvement of the ventral root. Case Description: A 72-year-old female with a 10-month history of Brown-Séquard–type monoparesis is described. On neurological examination, the left leg motor function was grade 3 or 4/5, and dysthesia with low pinprick sensation at the right side below the T8 and T9 dermatome was identified. There were no signs of multiple neurofibromatosis. Magnetic resonance imaging demonstrated a well-demarcated round mass with high enhancement and moderate peritumoral edema, but no combined syrinx. The mass (1.5 × 1 × 1.5 cm) was located at the anterior part of the spinal canal on the left of the midline of the T8 and T9 space. A left-sided unilateral approach was performed with osteoplastic laminotomy of T8 and T9 vertebrae, and radical removal of a subpial tumor was achieved. Pathological examination revealed subpial intramedullary schwannoma. The patient improved postoperatively and at discharge was able to walk without any support. Conclusion: The authors emphasize that the differential diagnosis of intramedullary schwannoma should be included when peritumoral edema is moderately present to provide appropriate preoperative preparations, even if a tumor is seemingly located in the intradural extramedullary space. [Copyright &y& Elsevier]

The purpose of this study was to identify central neuronal sites activated by stimulation of cardiac ischemia-sensitive afferent neurons and determine whether electrical stimulation of left vagal afferent fibers modified the pattern of neuronal activation. Fos-like immunoreactivity (Fos-LI) was used as an index of neuronal activation in selected levels of cervical and thoracic spinal cord and brain stem. Adult Sprague-Dawley rats were anesthetized with urethane and underwent intrapericardial infusion of an "inflammatory exudate solution" (IES) containing algogenic substances that are released during ischemia (10 mM adenosine, bradykinin, prostaglandin E2, and 5-hydroxytryptamine) or occlusion of the left anterior descending coronary artery (CoAO) to activate cardiac ischemia-sensitive (nociceptive) afferent fibers. IES and CoAO increased Fos-LI above resting levels in dorsal horns in laminae I-V at C2 and T4 and in the caudal nucleus tractus solitarius. Dorsal rhizotomy virtually eliminated Fos-LI in the spinal cord as well as the brain stem. Neuromodulation of the ischemic signal by electrical stimulation of the central end of the left thoracic vagus excited neurons at the cervical and brain stem level but inhibited neurons at the thoracic spinal cord during IES or CoAO. These results suggest that stimulation of the left thoracic vagus excites descending inhibitory pathways. Inhibition at the thoracic spinal level that suppresses the ischemic (nociceptive) input signal may occur by a short-loop descending pathway via signals from cervical propriospinal circuits and/or a longer-loop descending pathway via signals from the nucleus tractus solitarius. [ABSTRACT FROM AUTHOR]

The aims of this study were to examine effects of urinary bladder distension (UBD) on T3–T4 spinal neurons receiving cardiac and somatic noxious inputs and to determine the pathway involved in transmitting urinary bladder inputs to thoracic spinal segments. Extracellular potentials of single T3–T4 neurons were recorded in pentobarbital anesthetized male rats. Either bradykinin solution (10−5 M) or an algogenic mixture (adenosine 10−3 M, bradykinin, histamine, serotonin, prostaglandin E2 10−5 M each) was administered intrapericardially. UBD was produced by saline inflation (0.5–2.0 ml, 20 s). Of 487 neurons tested for responses to UBD, 70 were inhibited and 37 were excited. Seventy-six out of 336 neurons received convergent input from UBD and heart; 69/76 viscerovisceral convergent neurons had somatic fields. Spinal transection at rostral C1 abolished UBD inhibition in 5/9 neurons; whereas transections at L1–L2 abolished UBD inhibition in 3/3 cells tested. Results showed that T3–T4 spinal neurons processing cardiac and somatic nociceptive information were primarily inhibited by input from the urinary bladder through either supraspinal structures or direct intraspinal pathways. [Copyright &y& Elsevier]

The purposes of this study were to examine responses of superficial (depth <300 μm) and deeper thoracic spinal neurons to chemical stimulation of cardiac afferents and effects of descending influences on these neurons. Extracellular potentials of single T3–T4 neurons were recorded in pentobarbital anesthetized, paralyzed and ventilated male rats. A catheter was placed in the pericardial sac to administer 0.2 ml of a mixture of algogenic chemicals that contained adenosine (10−3 M), bradykinin, histamine, serotonin, prostaglandin E2 (10−5 M). Fifteen of 55 (27%) superficial neurons responsive to intrapericardial chemicals were compared to 80/169 (47%) deeper neurons. All 15 superficial neurons that responded to cardiac afferents were excited (E), whereas 66 deeper neurons were excited, ten were inhibited and four showed excitation–inhibition. Spontaneous activity of superficial neurons with short-lasting excitatory responses was significantly lower than that of deeper neurons (P<0.05). Somatic receptive fields on chest, axilla, arm and upper back areas were found for 77/95 (81%) neurons that responded to intrapericardial chemicals. The proportion of somatic field properties and their sizes in superficial neurons were similar to deeper neurons. After cervical spinal transection, both spontaneous activity and responses to chemical stimulation of cardiac afferents significantly increased in six out of six neurons excited by intrapericardial injections. Results showed that chemical stimulation of cardiac afferents excited superficial T3–T4 spinal neurons, whereas deeper neurons exhibited multiple patterns of responses. Some characteristics of subgroups of superficial neurons were quantitatively different from deeper neurons. Thoracic spinal neurons processing cardiac nociceptive information were under tonic descending inhibition. [Copyright &y& Elsevier]

Electrical stimulation of the spinal cord above the sacral segments was used to produce coordinated micturition in the paralysed decerebrate cat. Stimulation of the superficial aspect of the dorsolateral funiculus (DLF) within the lower thoracic (T9-T13) segments produced a bladder contraction coordinated with decreased activity in the external urethral sphincter (EUS) branch of the pudendal nerve during which time fluid was expelled. In addition, a similar response was observed with DLF stimulation at the boundary of the L5/L6 segments. At the second cervical spinal segment, however, stimulation of a more lateral and ventral portion of the superficial spinal white matter was the only effective site for producing micturition. The spinal cord-evoked response was comparable to the micturition evoked by electrical stimulation of the pontine micturition centre (PMC) within the brainstem. A bilateral lesion of the dorsal columns (DC) and the dorsolateral funiculi (DLF) at the lower thoracic levels abolished reflex micturition evoked by bladder distension. However stimulation rostral to the lesion, within the PMC or thoracic DLF, continued to produce coordinated bladder and sphincter response during voiding. Stimulation caudal to the lesion produced a decrease in pudendal nerve activity but did not produce a void or bladder pressure change. This reduction in pudendal nerve activity could be abolished with a second lesion of the superficial DLF caudal to the stimulation site. It was concluded that stimulation of the thoracic dorsolateral funiculus activates both ascending and descending fibres which can influence the bladder and/or sphincter muscles. The spinal cordevoked voiding was hypothesized to be due to activation of some portion of the ascending limb of the spinobulbospinal micturition reflex loop. The decreased activity produced by stimulation of the thoracic DLF caudal to a bilateral DC/DLF subtotal cord lesion may be mediated by fibres descending in the dorsolateral funiculus. The possibility that the spinal cord stimulation antidromically activated axons of neurons having segmental collaterals capable of influencing pudendal neural activity cannot be exclused at this time. [ABSTRACT FROM AUTHOR]